It's a shame that we live in a world where people are being financially stripped to their bones just to keep on living. Costs for medical treatment should be reasonable and affordable to everyone.
Have you tried calling Amazon's customer service (or being called by them)? Maybe they can do some kind of an exception if you explained them your situation? I'm afraid that indeed it will be difficult to sell something immediately unless offered for an unreasonable low price, which is not what you want and not what would really help you.
Anyway, best of wishes to you!